Index filicum,sive, Enumeratio omnium generum specierumque filicum et Hydropteridum ab anno 1753 ad finem anni 1905 descriptorium ? adjectis synonymis principalibus, area geographica, etc. /Carl Christensen.
- publisher: Hafniae [Copenhagen] : H. Hagerup,
- creator: Christensen, Carl,
- years: 1906.
- pages: lix, 744 p. ;
- download: pdf file
